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Blade Frenzy
http://heroes-newerth.com/wp-content/myimages/blade-frenzy.png
Swiftblade works himself into a blade frenzy.
While in this state, he gains Magic Immunity and
deals high damage per second to any nearby enemy units.
Swiftblade is free to move around even while this skill
is active.
Level 1 : 80 Damage per second for 5 seconds
Level 2 : 100 Damage per second for 5 seconds
Level 3 : 120 Damage per second for 5 seconds
Level 4 : 140 Damage per second for 5 seconds And the ability to attack at -50% attack speed
Mana cost 110
Cooldown 30/26/24/22 seconds

Explanation:This ability is one of the strongest early game abilities in the game. This is what makes you such a scary opponent to lane against as almost any hero when coupled with a slow or a stun. Be sure to wait to use this when you are already next to the hero you are attempting to kill so you can get the full damage of the spin. Also be sure to click next to the hero you are spinning on instead of on him. This is avoid pulling creep agro and your hero will follow more closely, making it more difficult to juke.
Note: This ability is also an excellent escape mechanism when combined with a Homecoming Stone

Explanation: This ability makes Swiftblade the most dangerous hero to encounter 1v1 in the woods. It gives him a long duration of invulnerability and insane damage output. It can easily turn a dangerous situation into an advantageous one for Swiftblade by moving away from creeps and ulting the enemy(s).
Note: You will continue to auto-attack throughout the duration of your ultimate, so on-hit effects will be applied, although not directly from your ultimate.

Explanation: Maxing your spin first allows you to maximize your early game damage output. It will net you more kills, allowing you to increase your farm significantly. Stats are taken over Way of the Sword at levels 2 and 4. This will increase your mana pool early, resulting in fewer moments where you find yourself out of mana and vulnerable. Since your spin is how you will be killing the heroes for about the first 7 levels (through the laning phase), the crit is relatively useless, as it will only give you about a bonus 60 damage given that you crit on the few auto attacks you might need to finish off your target. The extra mana from stats allows you to use your ultimate in conjunction with your spin at level 6 (you would otherwise not have enough mana). Leveling the crit next is important though, since you will be building damage items around this point. Counter Attack is most useful later game when you will have the health to be able to soak up damage and, consequently, counter attack more often. The ultimate is taken whenever possible.

Laning
Picking a good laning partner for Swiftblade is extremely important. Although he can be powerful with a spin alone, it generally will not be enough to kill a hero, and the chase can put him in dangeorous territory. Picking a stunner or a slower to lane with him will heavily increase his early success. Great early laning partners include:

Laning in the short lane (Top for Hellbourne, Bottom for Legion) is also important, as it gives him enough room to spin safely without entering tower range or being too far up and vulnerable to ganks.

Scoring first blood is quite easy with Swiftblade. Try to have your laning partner hide in the woods. Unwary opponents will generally move up with the creep wave. After your teammate stun/slows them, spin on top of them. Make sure your lane partner continues to auto attack them, as the spin will not do enough damage to kill them itself. A squishy target will GENERALLY be killed, but otherwise you will have done enough damage to make sure they stay back in their lane, allowing you to farm. Continue to scare back the opponents with slows and spins, and if they are not careful you should be able to net a few easy kills during the laning phase and have strong farm.

Last hit every creep possible. Early farm is important for Swiftblade to be able to snowball hard into the mid and late game.